CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit from Korean Patent Application No.
10-2015-0070981, filed on May 21, 2015, in the Korean Intellectual Property Office, the disclosure of which is incorporated
herein by reference in its entirety.
BACKGROUND
Field
[0002] Apparatuses and methods consistent with exemplary embodiments relate to an apparatus
and a method for outputting a content, and a display apparatus, and more particularly,
to an apparatus and a method for outputting a content to provide a high-definition
content, and a display apparatus.
Description of Related Art
[0003] Many display apparatuses are capable of playing High Dynamic Range (HDR) content.
However, content played on these display apparatuses is mainly produced as a Standard
Dynamic Range (SDR) content. Therefore, a technology that converts an SDR content
into a content having an HDR content characteristic has been studied. As a representative
example of this technology, there is a technology that converts an SDR content in
order to enable the SDR content to have an HDR content characteristic in a display
apparatus capable of playing an HDR content.
[0004] If an SDR content is input from a content outputting apparatus such as a Digital
Video Recorder (DVR) or a Blu-ray Disc (BD) player, a display apparatus capable of
playing an HDR content gamma-corrects the input SDR content by using gamma information
applicable to an HDR content to convert the SDR content into a content having a characteristic
of the HDR content.
[0005] However, if the display apparatus converts the input SDR content into the content
having the characteristic of the HDR content through an existing technology as described
above, the gamma information applied to the SDR content is not known. Therefore, the
SDR content is not accurately converted into the content having the characteristic
of the HDR content.
[0006] In other words, the display apparatus receives only a decoded SDR content and additional
information about the SDR content from the content outputting apparatus through an
interface such as a High Definition Multimedia Interface (HDMI). Therefore, the display
apparatus may not check the gamma information applied to the SDR content.
[0007] As a result, the display apparatus converts the SDR content into the content having
the characteristic of the HDR content by using gamma information applicable to the
display apparatus without considering the gamma information applied to the SDR content.
Therefore, the display apparatus displays a content, which is not correctly converted
from the received SDR content in order to have the characteristic of the HDR content,
on a screen.
SUMMARY
[0008] Exemplary embodiments may overcome the above disadvantages and other disadvantages
not described above. Also, exemplary embodiments are not required to overcome the
disadvantages described above, and an exemplary embodiment may not overcome any of
the problems described above.
[0009] Exemplary embodiments provide converting a Standard Dynamic Range (SDR) content into
a content corresponding to a High Dynamic Range (HDR) content outputtable on a display
apparatus.
[0010] According to an aspect of an exemplary embodiment, an apparatus for outputting a
content to a display includes a communicator configured to perform a data communication
with the display; an input interface configured to receive an input content and metadata
associated with the input content; and a processor configured to acquire image quality
information applied to the content based on the metadata, to convert the input content
into a converted content outputtable on the display by using content conversion information
related to the acquired image quality information, and to control the communicator
to output the converted content to the display.
[0011] The input content may include a Standard Dynamic Range (SDR) content, the image quality
information applied to the input content may include gamma information, and the converted
content outputtable on the display may include a High Dynamic Range (HDR) content.
[0012] The content conversion information may include a lookup table for converting SDR
pixel values of image frames of the SDR content into HDR pixel values having a characteristic
of the HDR content, wherein the display may be further configured to gamma-correct
the converted content by using gamma information predetermined to be applied to the
HDR content.
[0013] The HDR pixel values may correspond to the SDR pixel values of the image frames of
the SDR content, and the processor may be further configured to convert the SDR pixel
values of the image frames of the SDR content into the HDR pixel values based on the
lookup table.
[0014] The HDR pixel values may correspond to a subset of the SDR pixel values of the image
frames of the SDR content, and the processor may be further configured to determine
other HDR pixel values corresponding to other SDR pixel values from the HDR pixel
values corresponding to the subset of the SDR pixel values based on the lookup table.
[0015] The apparatus may further include a storage configured to store a plurality of pieces
of content conversion information corresponding to a plurality of pieces of gamma
information applicable to the SDR content, and the processor may be further configured
to acquire the content conversion information corresponding to the gamma information
from the storage.
[0016] The processor may be further configured to determine whether at least one from among
Video Usability Information (VUI) or Supplemental Enhancement Information (SEI) of
the metadata includes the gamma information applied to the SDR content.
[0017] In response to the at least one from among VUI or SEI of the metadata not including
the gamma information applied to the SDR content, the processor may be further configured
to determine the gamma information applied to the SDR content based on resolution
information of the SDR content based on the at least one from among VUI or SEI of
the metadata.
[0018] The processor may be further configured to control the communicator to transmit to
the display content information comprising information for gamma-correcting the converted
content in the display.
[0019] In response to Extended Display Identification Data (EDID) being received from the
display through the communicator, the processor may be further configured to determine
whether the display is capable of playing the HDR content based on the received EDID
and to convert the SDR content into the HDR content in response to determining that
the display is capable of playing the HDR content.
[0020] The apparatus may further include: a storage configured to store a plurality of pieces
of content conversion information corresponding to a plurality of pieces of gamma
information applicable to the SDR content, and the processor may be further configured
to acquire the content conversion information based on the acquired gamma information
and display gamma information included in the EDID received from the display.
[0021] According to another aspect of an exemplary embodiment, a method of outputting a
content from a content outputting apparatus to a display includes receiving an input
content and metadata associated with the input content; acquiring image quality information
applied to the input content based on the metadata; determining content conversion
information related to the acquired image quality information; converting the input
content into a converted content outputtable on the display using the content conversion
information; and outputting the converted content to the display.
[0022] The input content may include an SDR content, the image quality information applied
to the input content may include gamma information, and the converted content outputtable
on the display may include an HDR content.
[0023] The content conversion information may include a lookup table for converting SDR
pixel values of image frames of the SDR content into HDR pixel values having a characteristic
of the HDR content, and the display may gamma-correct the converted content by using
gamma information predetermined to be applied to the HDR content.
[0024] The HDR pixel values may correspond to the SDR pixel values of the image frames of
the SDR content, and the converting may further include converting the SDR pixel values
of the image frames of the SDR content into the HDR pixel values based on the lookup
table.
[0025] The HDR pixel values correspond to a subset of the SDR pixel values of the image
frames of the SDR content, and the converting may further include determining other
HDR pixel values corresponding to other SDR pixel values from the HDR pixel values
corresponding to the subset of the SDR pixel values based on the lookup table.
[0026] The acquiring may further include acquiring the content conversion information corresponding
to the gamma information from a plurality of pieces of content conversion information
corresponding to a plurality of pieces of gamma information applicable to a pre-stored
SDR content.
[0027] The acquiring may further include determining whether at least one from among Video
Usability Information (VUI) or Supplemental Enhancement Information (SEI) of the metadata
may include the gamma information applied to the SDR content.
[0028] The acquiring may further include, in response to at least one from among the VUI
or SEI of the metadata not including the gamma information, determining the gamma
information based on resolution information of the SDR content included in the VUI
or SEI.
[0029] The outputting may further include transmitting content information including information
for gamma-correcting the converted content in the display to the display.
[0030] The method may further include: in response to Extended Display Identification Data
(EDID) being received from the display, determining whether the display is capable
of playing the HDR content, based on the received EDID, and in response to a determination
that the display is capable of playing the HDR content, the SDR content may be converted
into the HDR content.
[0031] According to a further aspect of an exemplary embodiment, a display apparatus includes
a communicator configured to perform a data communication with a content outputting
apparatus; a display configured to display a content; and a processor configured to,
in response to the content being received from the content outputting apparatus through
the communicator, correct an image quality of the content using image quality information
predetermined to be applied to the content and control the display to display the
content having the corrected image quality, wherein the content is a content corresponding
to an HDR content.
[0032] According to a still further aspect of an exemplary embodiment, a content providing
apparatus includes a communicator configured to communicate with a display; an input
interface configured to receive a Standard Dynamic Range (SDR) content; and a processor
configured to determine gamma information associated with the input content, to determine
content conversion information related to the gamma information, to convert the SDR
content into High Dynamic Range (HDR) content using the content conversion information,
and to output the HDR content to the display.
[0033] Additional and/or other aspects and advantages of will be set forth in part in the
description which follows and, in part, will be obvious from the description, or may
be learned by practice of the exemplary embodiments.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0034] The above and/or other aspects of exemplary embodiments will be more apparent by
describing certain exemplary embodiments with reference to the accompanying drawings,
in which:
FIG. 1 illustrates a configuration of a content player system according to an exemplary
embodiment;
FIG. 2 is a block diagram of an apparatus for outputting a content, according to an
exemplary embodiment;
FIG. 3 is a detailed block diagram of an apparatus for outputting a content, according
to an exemplary embodiment;
FIG. 4 is a block diagram of a display apparatus according to an exemplary embodiment;
FIG. 5 illustrates content conversion information for converting a Standard Dynamic
Range (SDR) content into a content having a characteristic of a High Dynamic Range
(HDR) content, according to an exemplary embodiment;
FIG. 6 illustrates content conversion information for converting an SDR content into
a content having a characteristic of an HDR content, according to another exemplary
embodiment;
FIG. 7 illustrates Video Usability Information (VUI) or Supplemental Enhancement Information
(SEI) of metadata of an SDR content, according to an exemplary embodiment;
FIG. 8 illustrates conversions of SDR pixel values of an SDR content into HDR pixel
values based on content conversion information in a content outputting apparatus,
according to an exemplary embodiment;
FIG. 9 illustrates gamma curves depending on conversions of SDR pixel values of an
SDR content into HDR pixel values in a content outputting apparatus, according to
an exemplary embodiment;
FIG. 10 illustrates a reproduction of content conversion information based on luminance
information of a display apparatus in a content outputting apparatus, according to
an exemplary embodiment; and
FIG. 11 is a flowchart of a method of outputting a content from a content outputting
apparatus to a display apparatus, according to an exemplary embodiment.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0035] The exemplary embodiments of the present disclosure may be diversely modified. Accordingly,
specific exemplary embodiments are illustrated in the drawings and are described in
detail in the detailed description. However, it is to be understood that the present
disclosure is not limited to a specific exemplary embodiment, but includes all modifications,
equivalents, and substitutions without departing from the scope and spirit of the
present disclosure. Also, well-known functions or constructions are not described
in detail since they would obscure the disclosure with unnecessary detail.
[0036] The terms used in the present application are only used to describe the exemplary
embodiments, but are not intended to limit the scope of the disclosure. The singular
expression also includes the plural meaning as long as it does not differently mean
in the context. In the present application, the terms "include" and "consist of" designate
the presence of features, numbers, steps, operations, components, elements, or a combination
thereof that are written in the specification, but do not exclude the presence or
possibility of addition of one or more other features, numbers, steps, operations,
components, elements, or a combination thereof.
[0037] In the exemplary embodiment of the present disclosure, a "module" or a "unit" performs
at least one function or operation, and may be implemented with hardware, software,
or a combination of hardware and software. In addition, a plurality of "modules" or
a plurality of "units" may be integrated into at least one module except for a "module"
or a "unit" which has to be implemented with specific hardware, and may be implemented
with at least one processor (not shown).
[0038] Certain exemplary embodiments will now be described in greater detail with reference
to the accompanying drawings.
[0039] In the following description, same drawing reference numerals are used for the same
elements even in different drawings. The matters defined in the description, such
as detailed construction and elements, are provided to assist in an understanding
of the exemplary embodiments. Thus, it is apparent that the exemplary embodiments
can be carried out without those specifically defined matters. Also, well-known functions
or constructions are not described in detail since they would obscure the exemplary
embodiments with unnecessary detail.
[0040] FIG. 1 illustrates a configuration of a content player system according to an exemplary
embodiment.
[0041] As shown in FIG. 1, the content player system includes a content outputting apparatus
100 and a display apparatus 200.
[0042] The content outputting apparatus 100 is an apparatus that reads a content stored
on a recording medium, such as a Digital Video Disc (DVD) or a Blue-ray disc (BD),
and outputs the read content to the display apparatus 200. In particular, if the content
stored on the recording medium, such as the DVD or the BD disc, is a Standard Dynamic
Range (SDR) content, the content outputting apparatus 100 converts the SDR content
into a content corresponding to a High Dynamic Range (HDR) content and outputs the
converted content to the display apparatus 200.
[0043] The display apparatus 200 may be a display apparatus such as a smart TV and may display
the content output from the content outputting apparatus 100 on a screen. The display
apparatus 200 may be an apparatus capable of playing an HDR content. Therefore, if
the content corresponding to the HDR content is received from the content outputting
apparatus 100, the display apparatus 200 may gamma-correct the content corresponding
to the HDR content received from the content outputting apparatus 100 by using gamma
information preset to be applied to the HDR content, and display the gamma-corrected
content on the screen.
[0044] According to an exemplary embodiment, if an SDR content stored on a recording medium,
such as a DVD or a BD, is input, the content outputting apparatus 100 acquires gamma
information applied to the SDR content with reference to metadata of the input SDR
content. The content outputting apparatus 100 converts the SDR content into a content
corresponding to an HDR content outputtable on the display apparatus 200 based on
content conversion information related to the acquired gamma information among pre-stored
content conversion information. The content outputting apparatus 100 transmits the
content, which is converted to be outputtable on the display apparatus 200, to the
display apparatus 200.
[0045] Therefore, the display apparatus 200 may gamma-correct the content received from
the content outputting apparatus 100 based on the gamma information preset to be applied
to the HDR content and display the gamma-corrected content.
[0046] According to another exemplary embodiment, if an SDR content stored on a recording
medium, such as a DVD or a BD, is input, the content outputting apparatus 100 acquires
gamma information applied to the SDR content with reference to metadata of the input
SDR content. The content outputting apparatus 100 converts the SDR content into a
content corresponding to an HDR content outputtable on the display apparatus 200 based
on content conversion information related to the acquired gamma information among
pre-stored content conversion information. The content outputting apparatus 100 transmits
a content, which is converted to be outputtable on the display apparatus 200, and
content conversion information applied to the corresponding content to the display
apparatus 200.
[0047] Therefore, the display apparatus 200 may gamma-correct a content received from the
content outputting apparatus 100 by using gamma information related to content conversion
information received from the content outputting apparatus 100 and display the gamma-corrected
content.
[0048] According to another exemplary embodiment, if an SDR content recorded on a recording
medium such as a DVD or a BD is input, the content outputting apparatus 100 acquires
gamma information applied to the SDR content with reference to metadata of the input
SDR content. The content outputting apparatus 100 may receive Extended Display Identification
Data (EDID) information from the display apparatus 200. Here, the EDID information
may include gamma information preset to be applied to an HDR content in the display
apparatus 200. If the EDID information is received, the content outputting apparatus
100 converts the SDR content into a content corresponding to an HDR content outputtable
on the display apparatus 200, based on acquired gamma information of pre-stored content
conversion information and gamma information of the received EDID information. The
content outputting apparatus 100 transmits the content, which is converted to be outputtable
on the display apparatus 200, to the display apparatus 200.
[0049] Therefore, the display apparatus 200 may gamma-correct a content received from the
content outputting apparatus 100 by using gamma information related to content conversion
information received from the content outputting apparatus 100 and display the gamma-corrected
content.
[0050] Elements of the content player system according to exemplary embodiments have been
respectively briefly described. Some exemplary embodiments of the content outputting
apparatus 100 will now be described in detail.
[0051] FIG. 2 is a block diagram of a content outputting apparatus 100, according to an
exemplary embodiment. FIG. 3 is a detailed block diagram of the content outputting
apparatus 100, according to an exemplary embodiment.
[0052] As shown in FIG. 2, the content outputting apparatus 100 includes an input interface
110, a communicator 120, a processor 130, and a storage 140.
[0053] The input interface 110 receives a content recorded on a recording medium such as
a DVD or a BD and metadata of the corresponding content. Here, the content is an SDR
content, and the metadata may include Video Usability Information (VUI) or Supplemental
Enhancement Information (SEI) including at least one selected from encoding information
of the SDR content, gamma information applied to the SDR content, resolution information,
and up-scale ratio information.
[0054] The communicator 120 performs a data communication with the display apparatus 200
that plays a content. Here, the display apparatus 200 may be a display apparatus capable
of playing an HDR content. Therefore, the communicator 120 may perform the data communication
with the display apparatus 200 and transmit a content, which is converted to correspond
to the HDR content in relation to the SDR content, to the display apparatus 200.
[0055] The communicator 120 may perform communication by wire or wirelessly to perform the
data communication with the display apparatus 200. In this case, the communicator
120 may include a short-range communication module 121, a wireless communication module
123, and a wired communication module 125.
[0056] The short-range communication module 121 may wirelessly perform a short-range communication
with the display apparatus 200 and include at least one selected from a Bluetooth
module, an Infrared Data Association (IrDA) module, a Near Field Communication (NFC)
module, a WiFi module, and a Zigbee module.
[0057] The wireless communication module 123 is a module that is connected to an external
network to perform communications according to a wireless communication protocol such
as Institute of Electrical and Electronics Engineers (IEEE) or the like. In other
words, the wireless communication module 123 may be a mobile communication module
that accesses a mobile communication network to perform communications according to
various types of communication standards such as 3
rd Generation (3G), 3
rd Generation Partnership Project (3GPP), Long Term Evolution (LTE), etc.
[0058] The wired communication module 125 may be an interface module that transmits a content
converted to correspond to an HDR content to the display apparatus 200 connected through
a wire cable according to a control command of the processor 130. The wired communication
module 125 may be realized through a High Definition Multimedia Interface (HDMI),
a Universal Serial Bus (USB), IEEE 1394, or the like.
[0059] The processor 130 acquires gamma information applied to an SDR content, which is
input along with corresponding metadata, based on the metadata input through the input
interface 110. The processor 130 converts the SDR content into a content corresponding
to an HDR content outputtable on the display apparatus 200 by using content conversion
information pre-stored in relation to the acquired gamma information and outputs the
corresponding content to the communicator 120. Therefore, the communicator 120 may
transmit the content, which is converted to correspond to the HDR content outputtable
on the display apparatus 200 in relation to the SDR content, to the display apparatus
200.
[0060] If the content converted to correspond to the HDR content is received from the content
outputting apparatus 100, the display apparatus 200 may gamma-correct the content
received from the content outputting apparatus 100 by using gamma information preset
to be applied to the HDR content, signal-process the gamma-corrected content in a
form that may be output, and display the signal-processed content on a screen.
[0061] In detail, as shown in FIG. 3, if an SDR content and metadata of the SDR content
are input through the input interface 110, a data processor 150 decodes the SDR content
based on the input metadata. Here, the metadata may include VUI or SEI including at
least one selected from encoding information of the SDR content, gamma information
applied to the SDR content, resolution information, and up-scale ratio information.
[0062] According to an exemplary embodiment, a BD may include an SDR content that is encoded
through a codec having a MPEG-2, H.264/MPEG-4 AVC, or VC-1 standard. Therefore, the
data processor 150 may decode the input SDR content based on the encoding information
of the metadata of the SDR content input through the input interface 110.
[0063] The processor 130 may determine whether the VUI or SEI of the metadata of the SDR
content input through the input interface 110 includes the gamma information applied
to the SDR content. If it is determined that the VUI or SEI includes the gamma information
applied to the SDR content, the processor 130 acquires the gamma information included
in the VUI or SEI and converts the SDR content into a content corresponding to the
HDR content outputtable on the display apparatus 200 by using content conversion information
pre-stored in relation to the acquired gamma information.
[0064] Here, the content conversion information may be a lookup table for converting SDR
pixel values of each image frame of the input SDR content into HDR pixel values having
a characteristic of the HDR content outputtable on the display apparatus 200. Therefore,
if the gamma information applied to the SDR content is acquired from the VUI or SEI
included in the metadata of the input SDR content, the processor 130 converts SDR
pixel values of each image frame of the decoded SDR content into HDR pixel values
having the characteristic of the HDR content outputtable on the display apparatus
200 by using the content conversion information pre-stored in relation to the acquired
gamma information.
[0065] According to an exemplary embodiment, HDR pixel values having a characteristic of
an HDR content outputtable on the display apparatus 200 may be set to respectively
correspond to SDR pixel values of each image frame of the SDR content. For example,
SDR pixel values of an 8-bit image content may exist between 0 and 255. In this case,
HDR pixel values may set to respectively correspond to SDR pixel values. Therefore,
the processor 130 may convert the SDR content into a content having the characteristic
of the HDR content outputtable on the display apparatus 200, by using HDR pixel values
respectively corresponding to SDR pixel values of each image frame of the SDR content
based on the lookup table that is the content conversion information.
[0066] According to another exemplary embodiment, HDR pixel values having a characteristic
of an HDR content outputtable on the display apparatus 200 may be set to correspond
to some SDR pixel values of each image frame of the SDR content. For example, SDR
pixel values of an 8-bit image content may exist between 0 and 255, and HDR pixel
values may be set to correspond to some of the SDR pixel values. In this case, the
processor 130 may perform interpolation processing to determine HDR pixel values corresponding
to other SDR pixel values based on the HDR pixel values corresponding to some of the
SDR pixel values based on the lookup table that is the content conversion information.
[0067] For example, in the lookup table, a 0
th HDR pixel value may be set to correspond to a 0
th SDR pixel value, and a fourth HDR pixel value may be set to correspond to a fourth
SDR pixel value. In this case, the processor 130 may determine HDR pixel values respectively
corresponding to other SDR pixel values (i.e., first through third SDR pixel values)
by using an arbitrary interpolation method of the 0
th and fourth HDR pixel values.
[0068] If SDR pixel values of each image frame of an SDR content are determined as described
above, the processor 130 may convert the SDR content into a content having a characteristic
of an HDR content outputtable on the display apparatus 200 by using HDR pixel values
respectively corresponding to SDR pixel values of each image frame of the SDR content.
[0069] Therefore, if a content that is converted into HDR pixel values is received from
the content outputting apparatus 100, the display apparatus 200 may gamma-correct
the received content by using gamma information preset to be applied to an HDR content,
signal-process the gamma-corrected content in a form that may be output, and display
the signal-processed content.
[0070] The content conversion information described above may be stored in the storage 140.
The storage 140 may store content conversion information respectively corresponding
to a plurality of pieces of gamma information applicable to the SDR content. HDR pixel
values that are set to correspond to SDR pixel values on a one-to-one basis or correspond
to some of the SDR pixel values may be calculated by a predefined conversion expression
in relation to a plurality of pieces of gamma information applicable to the SDR content
without additional color processing. Therefore, the storage 140 may store content
conversion information matching with the SDR pixel values of the SDR content and the
HDR pixel values calculated to correspond to the SDR pixel values according to each
of the plurality of pieces of gamma information applicable to the SDR content.
[0071] The storage 140 may also store an operating system (OS) necessary for operating the
display apparatus 200, various types of programs or data, etc. Also, the storage 140
may perform a data communication with the display apparatus 200 through the communicator
120 to store output resolution information of the display apparatus 200 and various
types of data such as gamma information, etc.
[0072] Therefore, if the gamma information applied to the SDR content is acquired from the
VUI or SEI included in the metadata of the input SDR content, the processor 130 may
acquire content conversion information related to pre-acquired gamma information from
content conversion information of each of the plurality of pieces of gamma information
applicable to the SDR content stored in the storage 140. The processor 130 may determine
HDR pixel values corresponding to SDR pixel values of each image frame of the decoded
SDR content from the acquired convent conversion information. Here, the SDR pixel
values of each image frame may be pixel values that are within a range where an image
quality having a maximum brightness of about 100 nit (Cd/m2) level in a general content
standard may be realized. For example, 8-bit SDR pixel values may be values at which
pixel expressions are possible within pixel values between 0 and 255.
[0073] The processor 130 may convert the SDR content into a content having the characteristic
of the HDR content outputtable on the display apparatus 200 by using HDR pixel values
respectively corresponding to SDR pixel values of each image frame of the SDR content
and transmit the content to the display apparatus 200.
[0074] If the gamma information applied to the SDR content does not exist in the VUI or
SEI of the metadata of the input SDR content, the processor 130 may determine gamma
information of the SDR content based on resolution information of the SDR content
included in the metadata. For example, gamma information of ITU-R BT.1886 or ITU-R
BT.1361 may be set for an SDR content having a high resolution such as Full High-Definition
(FHD) or High-Definition (HD). Gamma information of SMPTE 170M-2004 or ITU-R BT.1358
may set for an SDR content having a low resolution such as Standard Definition (SD).
[0075] Therefore, the processor 130 may determine gamma information related to the resolution
information included in the VUI or SEI from gamma information preset for each resolution
and acquire content conversion information related to the determined gamma information.
The processor 130 determines HDR pixel values corresponding to SDR pixels of each
image frame of the decoded SDR content from the acquired content conversion information.
The processor 130 converts the SDR content into a content having the characteristic
of the HDR content outputtable on the display apparatus 200 by using the HDR pixel
values respectively corresponding to the SDR pixel values of each image frame of the
SDR content and transmits the content to the display apparatus 200.
[0076] Here, the processor 130 may transmit content information including information(gamma
information) for gamma-correcting the corresponding content in the display apparatus
200 along with the content converted to have the characteristic of the HDR content
to the display apparatus 200. Therefore, the display apparatus 200 may gamma-correct
the content converted to have the characteristic of the HDR content based on gamma
information included in content information received from the content outputting apparatus
100, signal-process the gamma-corrected content in a form that may be output, and
display the signal-processed content.
[0077] However, the exemplary embodiments are not limited thereto, and the processor 130
may transmit content information including null information for gamma-correcting the
corresponding content in the display apparatus 200 to the display apparatus 200 along
with the content converted to have the characteristic of the HDR content. If the content
information including the null information is received, the display apparatus 200
may gamma-correct the content converted to have the characteristic of the HDR content
by using default gamma information, signal-process the gamma-corrected content in
a form that may be output, and display the signal-processed content.
[0078] The processor 130 may receive EDID from the display apparatus 200 through the communicator
120. Here, the EDID may be content playing-related spec information of the display
apparatus 200. If the EDID is received, the processor 130 may determine whether the
display apparatus 200 is capable of playing the HDR content, based on the received
EDID before converting the SDR content into the content having the characteristic
of the HDR content and, if it is determined that the display apparatus 200 is capable
of playing the HDR content, convert the SDR content into the content having the characteristic
of the HDR content.
[0079] The EDID received from the display apparatus 200 may include information for gamma-correcting
the HDR content. In this case, the processor 130 may acquire content conversion information
based on gamma information acquired from the VUI or SEI of the metadata of the SDR
content and the gamma information included in the EDID from a plurality of pieces
of content conversion information pre-stored in the storage 140. The processor 130
determines HDR pixel values corresponding to SDR pixel values of each image frame
of the decoded SDR content from the acquired content conversion information. The processor
130 converts the SDR content into a content having the characteristic of the HDR content
outputtable on the display apparatus 200 by using the HDR pixel values respectively
corresponding to the SDR pixel values of each image frame of the SDR content and transmits
the content to the display apparatus 200.
[0080] Therefore, the display apparatus 200 may gamma-correct the content converted to have
the characteristic of the HDR content received from the content outputting apparatus
100 by using preset gamma information, signal-process the gamma-corrected content
in a form that may be output, and display the signal-processed content.
[0081] Elements of the display apparatus 200 will now be described in detail.
[0082] FIG. 4 is a block diagram of a display apparatus according to an exemplary embodiment.
[0083] As shown in FIG. 4, the display apparatus 200 includes a communicator 210, a display
220, and a processor 230.
[0084] The communicator 210 performs a data communication with the content outputting apparatus
100 to receive a content from the content outputting apparatus 100. Here, the content
received from the content outputting apparatus 100 may be a content that is converted
into a content corresponding to an HDR content. The communicator 210 may be realized
as various types of communication modules as described with reference to FIG. 3.
[0085] The display 220 may be an element that displays various types of data processed according
to a control command of the processor 230 and a content signal-processed in relation
to the content received through the communicator 210 on a screen. The display 220
may be, for example, an all-in-one type with a touch panel for receiving a touch command
of a user. In this case, the display 220 may display the various types of data processed
according to the control command of the processor 230 and the signal-processed content
on the screen and receive the touch command of the user through the touch panel.
[0086] If the content is received from the content outputting apparatus 100 through the
communicator 210, the processor 230 corrects an image quality of the corresponding
content by using image quality information preset to be applied to the received content.
The processor 230 signal-processes the image-quality-corrected content in a form that
may be output and controls the display 220 to display the signal-processed content.
[0087] According to an exemplary embodiment, if a content corresponding to an HDR content
is received through the communicator 210, the processor 230 gamma-corrects the content
corresponding to the HDR content received from the content outputting apparatus 100,
by using gamma information preset to be applied to the HDR content. The processor
230 may signal-process the gamma-corrected content in a form that may be output and
display the signal-processed content through the display 220.
[0088] According to another exemplary embodiment, the content outputting apparatus 100 may
transmit a content converted to be outputtable on the display apparatus 200 and content
conversion information applied to the corresponding content to the display apparatus
200. If the content and the content conversion information applied to the content
are received, the processor 230 acquires gamma information related to the received
content conversion information from a plurality of pieces of pre-stored gamma information
and gamma-corrects the content received from the content outputting apparatus 100
based on the acquired gamma information. The processor 230 may signal-process the
gamma-corrected content in a form that may be output and display the signal-processed
content through the display 220.
[0089] As shown in FIG. 3, the content outputting apparatus 100 may further include a user
input interface 160. The user input interface 160 may receive a user command from
a remote control device (not shown) that controls an operation of the content outputting
apparatus 100. In detail, the remote control device may transmit a user command, such
as a content execution command, a function setting command of the content outputting
apparatus 100, or the like, to the content outputting apparatus 100 through a control
signal such as an infrared (IR) signal, a radio frequency (RF) signal, or the like.
Therefore, the user input interface 160 may execute the content based on a control
signal received through the remote control device or may set a function corresponding
to the control signal.
[0090] Content conversion information according to some exemplary embodiments will now be
described in detail.
[0091] FIG. 5 illustrates content conversion information for converting an SDR content into
a content having a characteristic of an HDR content, according to an exemplary embodiment.
FIG. 6 illustrates content conversion information for converting an SDR content into
a content having a characteristic of an HDR content, according to another exemplary
embodiment.
[0092] As described above, the storage 140 may store a lookup table that is content conversion
information respectively corresponding to a plurality of pieces of gamma information
applicable to an SDR content.
[0093] For example, SDR pixel values of each of R, G, and B pixels of an 8-bit SDR content
may exist between 0 and 255, and first gamma information of a plurality of pieces
of gamma information applicable to the SDR content may be applied to the SDR content.
As shown in FIG. 5, SDR pixel values R0 through R255 corresponding to R pixels of
the 8-bit SDR content, to which the first gamma information is applied, may be stored
in a lookup table 410. HDR pixel values R'0 through R'255 respectively corresponding
to the SDR pixel values R0 through R255 of the R pixels of the 8-bit SDR content may
match with the SDR pixel values R0 through R255 corresponding to the R pixels and
then may be stored in the lookup table 410. Here, the HDR pixel values R'0 through
R'255 may be values for gamma-correcting an SDR convent converted to have a characteristic
of an HDR content by using first gamma information of a plurality of pieces of gamma
information applicable to the HDR content.
[0094] In other words, the lookup table 410 may store 256 SDR pixel values R0 through R255
of the 8-bit SDR content to which the first gamma information is applied and the HDR
pixel values R'0 through R'255 that are calculated to respectively correspond to the
SDR pixel values R0 through R255 in order to gamma-correct the content converted to
have the characteristic of the HD content in relation to the SDR content by using
the first gamma information. Here, the SDR pixel values R0 through R255 match with
the HDR pixel values R'0 through R'255 on a one-to-one basis and then stored in the
storage 140.
[0095] Therefore, the processor 130 may extract HDR pixel values corresponding to SDR pixel
values of each image frame of the SDR content to which the first gamma information
is applied, by using the lookup table 410 pre-stored in the storage 140 and convert
the SDR content into a content having a characteristic of the HDR content outputtable
on the display apparatus 200 based on the extracted HDR pixel values.
[0096] As shown in FIG. 6, a lookup table 510 may store SDR pixel values R0, R5, R10, ...,
and R255 of SDR pixel values R0 through R255 of a 8-bit SDR content between 0 and
255, wherein first gamma information is applied to the 8-bit SDR content, and the
SDR pixel values R0, R5, R, 10, ..., and R 255 are set using a five-unit interval.
Also, HDR pixel values R'0, R'5, R'10, ..., and R'255 respectively corresponding to
the SDR pixel values R0, R5, R10, ..., and R 255 set using the five-unit interval
may match with the SDR pixel values R0, R5, R10, ..., and R255 and then stored in
the lookup table 510. Here, the HDR pixel values R'0, R'5, R'10, ..., and R'255 may
be values for gamma-correcting the SDR content converted to have a characteristic
of an HDR content by using first gamma information of a plurality of pieces of gamma
information applicable to the HDR content.
[0097] In other words, the lookup table 510 may store 52 SDR pixel values R0, R5, R10, ...,
and R255 of the 8-bit SDR content to which the first gamma information is applied
and the HDR pixel values R'0, R'5, R'10, ..., and R'255 that are calculated to respectively
correspond to the SDR pixel values R0, R5, R10, ..., and R255 in order to gamma-correct
the content converted to have the characteristic of the HDR content in relation to
the SDR content by using first gamma information. Here, the SDR pixel values R0, R5,
R10, ..., and R255 match with the HDR pixel values R'0, R'5, R'10, ..., and R'255
and are then stored in the storage 140.
[0098] As described above, the lookup table 510 may store some of 256 SDR pixel values of
an 8-bit SDR content and HDR pixel values respectively corresponding to some SDR pixel
values to efficiently use a memory size of the storage 140.
[0099] The processor 130 extracts HDR pixel values corresponding to some of the SDR pixel
values of each image frame of an SDR content to which first gamma information is applied,
by using the lookup table 510 pre-stored in the storage 140. The processor 130 may
determine HDR pixel values corresponding to other SDR pixel values based on the extracted
HDR pixel values. For example, if HDR pixel value R'0 and HDR pixel value R'5 are
extracted, the processor 130 may determine HDR pixel values R'1 through R'4 by using
any desired interpolation method of the HDR pixel values R'0 and R'5. As described
above, if HDR pixel values respectively corresponding to SDR pixel values of each
image frame of an SDR content are extracted and determined, the processor 130 may
convert the SDR content into a content having a characteristic of an HDR content outputtable
on the display apparatus 200, based on the HDR pixel values respectively corresponding
to the SDR pixel values.
[0100] FIG. 7 illustrates VUI or SEI of metadata of an SDR content, according to an exemplary
embodiment.
[0101] The metadata of the SDR content shown in FIG. 7 indicates that the SDR content is
produced based on an H.264 codec and includes VUI or SEI 610. As described above,
the VUI or SEI 610 may include at least one selected from encoding information of
the SDR content, gamma information applied to the SDR content, resolution information,
and up-scale ratio information.
[0102] Therefore, the processor 130 may acquire the gamma information applied to the SDR
content from the VUI or SEI 610 included in the metadata. As shown in FIG. 6, the
VUI or SEI 610 may include National Television System Committee (NTSC) standard gamma
value 2.2. This case indicates that gamma information about standard gamma value 2.2
is applied to the SDR content. Therefore, the processor 130 may convert the SDR content
into a content having an HDR content outputtable on the display apparatus 200 by using
a lookup table of content conversion information corresponding to gamma information
of gamma value 2.2 among content conversion information corresponding to a plurality
of pieces of gamma information applicable to the SDR content pre-stored in the storage
140.
[0103] The VUI or SEI 610 may include Phase Alternation Line (PAL) standard gamma value
2.8. This case indicates that gamma information of standard gamma value 2.8 is applied
to the SDR content. Therefore, the processor 130 may convert the SDR content into
a content having a characteristic of an HDR content outputtable on the display apparatus
200, by using a lookup table of content conversion information corresponding to gamma
information of gamma value 2.8 among content conversion information corresponding
to a plurality of pieces of gamma information applicable to the SDR content pre-stored
in the storage 140.
[0104] FIG. 8 illustrates a conversion of SDR pixel values of an SDR content into HDR pixel
values based on content conversion information in a content outputting apparatus,
according to an exemplary embodiment. FIG. 9 illustrates gamma curves depending on
conversions of SDR pixel values of an SDR content into HDR pixel values in a content
outputting apparatus, according to an exemplary embodiment.
[0105] As described with reference to FIGS. 5 and 6, SDR pixel values R, G, and B of an
8-bit SDR content may exist between 0 and 255, and first gamma information of a plurality
of pieces of gamma information applicable to the SDR content may be applied to the
SDR content. The SDR pixel values R, G, and B of the 8-bit SDR content, to which the
first gamma information is applied and which are between 0 and 255, or some of the
SDR pixel values R, G, and B may be stored in a lookup table that is content conversion
information. HDR pixel values R', G', and B' respectively corresponding to the SDR
pixel values R, G, and B of the 8-bit SDR content between 0 and 255 or some of the
SDR pixel values R, G, and B may match with the SDR pixel values R, G, and B pre-stored
in a lookup table and then stored in the lookup table.
[0106] If a lookup table related to gamma information of an input SDR content is detected
from lookup tables, the processor 130 may extract HDR pixel values R', G', and B'
corresponding to SDR pixel values R, G, and B of each image frame of the SDR content
by using the detected lookup table.
[0107] As shown in FIG. 8, particular SDR pixel values R, G, and B of each image frame of
an SDR content may be 129, 52, and 87, and HDR pixel values R, G, and B 129, 52, and
87 may be detected from a lookup table in relation to the particular SDR pixel values
R, G, and B 129, 52, and 87. If HDR pixel values corresponding to SDR pixel values
of each image frame of an SDR content are extracted through the above-described method,
the processor 130 converts the SDR pixel values of each image frame of the SDR content
into HDR pixel values corresponding to the SDR pixel values. Therefore, the SDR content
may be converted into a content having a characteristic of an HDR content outputtable
on the display apparatus 200.
[0108] In some exemplary embodiments, as shown in FIG. 9, if NTSC standard gamma value 2.2
is applied to an SDR content, a gamma curve of the SDR content may be formed as a
nonlinear gamma curve 810. The processor 130 may extract HDR pixel values R', G' and
B' corresponding to some of SDR pixel values R, G, and B of each image frame of the
SDR content based on a lookup table related to standard gamma value 2.2 (820). The
processor 130 may perform interpolation-processing to determine HDR pixel values R',
G', and B' corresponding to other SDR pixel values R, G, and B from the HDR pixel
values R', G', and B' corresponding to the SDR pixel values R, G, and B. If the HDR
pixel values R', G', and B' corresponding to the SDR pixel values R, G, and B of each
image frame of the SDR content are detected through a series of processes described
above (830), the processor 130 may convert the SDR content into a content having a
characteristic of an HDR content based on an HDR gamma curve 840 that is generated
based on the HDR pixel values R', G', and B' corresponding to the SDR pixel values
R, G, and B of each image frame of the SDR content.
[0109] FIG. 10 illustrates content conversion information that is reproduced based on luminance
information of a display apparatus in a content outputting apparatus, according to
an exemplary embodiment.
[0110] Content conversion information stored in the storage 140 may store gamma information
applied to an SDR content, SDR pixel values of each image frame of the SDR content,
and HDR pixel values respectively corresponding to the SDR pixel values. Here, the
SDR pixel values and the HDR pixel values match based on maximum luminance information
of the display apparatus 200 and then are stored in the content conversion information.
[0111] In some exemplary embodiments, the content conversion information may store the SDR
pixel values of the SDR content and the HDR pixel values respectively corresponding
to the SDR pixel values, wherein the SDR pixel values and the HDR pixel values match
and then are stored in the content conversion information. Here, the HDR pixel values
may be values that are calculated in consideration of maximum luminance value 2000
nit of the display apparatus 200. When the content conversion information is pre-stored
in the storage 140, luminance information indicating maximum luminance value 1000
nit or maximum luminance value 3000 nit may be received from the display apparatus
200.
[0112] According to exemplary embodiments, if luminance information indicating luminance
value 1000 nit is received from the display apparatus 200, the processor 130 may adjust
HDR pixel values respectively corresponding to SDR pixel values stored in content
conversion information to be higher than or equal to a threshold value corresponding
to a preset extension condition. Therefore, the processor 130 may convert the SDR
content into a content having a characteristic of an HDR content based on extended
content conversion information having a gamma curve 920 having a larger gradient than
a gamma curve 910 of the pre-stored content conversion information.
[0113] If luminance information indicating maximum luminance value 3000 nit is received
from the display apparatus 200, the processor 130 may adjust the HDR pixel values
respectively corresponding to the SDR pixel values stored in the content conversion
information to be lower than the threshold value corresponding to the preset extension
condition. Therefore, the processor 130 may convert the SDR content into a content
having a characteristic of an HDR content based on extended content conversion information
having a gamma curve 930 having a lower gradient than the gamma curve 910 of the pre-stored
content conversion information.
[0114] An operation of the content outputting apparatus 100 converting an SDR content into
a content having a characteristic of an HDR content outputtable on the display apparatus
200 has been described. Hereinafter, a method of converting an SDR content into a
content having a characteristic of an HDR content outputtable on the display apparatus
200 in the content outputting apparatus 100 according to exemplary embodiments will
be described in detail, according to some exemplary embodiments.
[0115] FIG. 11 is a flowchart of a method of outputting a content from a content outputting
apparatus to a display apparatus, according to an exemplary embodiment.
[0116] As shown in FIG. 11, in operation S1010, the content outputting apparatus 100 receives
an SDR content stored on a recording medium such as a DVD or a BD and metadata of
the SDR content. Here, the metadata may include VUI or SEI including at least one
selected from encoding information of the SDR content, gamma information applied to
the SDR content, resolution information, and up-scale ratio information.
[0117] If the SDR content and the metadata of the SDR content are input, the content outputting
apparatus 100 determines whether the VUI or SEI included in the input metadata includes
gamma information applied to the SDR content in operation S1020.
[0118] If it is determined in operation S1020 that the VUI or SEI included in the metadata
includes the gamma information applied to the SDR content, the content outputting
apparatus 100 acquires the gamma information applied to the SDR content from the VUI
or SEI and acquires content conversion information related to the acquired gamma information
in operation S1030.
[0119] Here, the content conversion information may be a lookup table for converting SDR
pixel values of each image frame of the input SDR content into HDR pixel values having
a characteristic of an HDR content outputtable on the display apparatus 200. The content
conversion information may be set in order to respectively correspond to a plurality
of pieces of gamma information applicable to the SDR content. The content conversion
information respectively corresponding to the plurality of pieces of gamma information
may be stored in a storage unit of the content outputting apparatus 100.
[0120] If the gamma information applied to the SDR content is acquired from the VUI or SEI
included in the metadata of the input SDR content, the content outputting apparatus
100 may acquire content conversion information related to the acquired gamma information
from a plurality of pieces of pre-stored content conversion information.
[0121] If it is determined in operation S1020 that the VUI or SEI included in the metadata
does not include the gamma information applied to the SDR content, the content outputting
apparatus 100 acquires content conversion information based on resolution information
of the SDR content included in the VUI or SEI in operation S1040. In detail, the content
outputting apparatus 100 determines the gamma information applied to the SDR content
based on the resolution information of the SDR content included in the VUI or SEI.
For example, gamma information of ITU-R BT.1886 or ITU-R BT.1361 may be set for an
SDR content having a high resolution such as FHD or HD, and gamma information of SMPTE
170M-2004 or ITU-R BT.1358 may be set for an SDR content having a low resolution such
as SD.
[0122] Therefore, the content outputting apparatus 100 determines the gamma information
related to the resolution information included in the VUI or SEI from gamma information
preset according to each resolution. The content outputting apparatus 100 may acquire
content conversion information corresponding to the gamma information related to the
resolution information from content conversion information pre-stored in order to
correspond to a plurality of pieces of gamma information applicable to the SDR content.
[0123] If the content conversion information is acquired based on the gamma information
or the resolution information included in the VUI or SEI, the content outputting apparatus
100 converts the SDR content into a content corresponding to an HDR content outputtable
on the display apparatus 200, by using the acquired content conversion information
in operation S1050.
[0124] As described above, the content conversion information may be a lookup table for
converting SDR pixel values of each image frame of an input SDR content into HDR pixel
values having a characteristic of an HDR content outputtable on the display apparatus
200. Therefore, the content outputting apparatus 100 converts the SDR pixel values
of each image frame of the SDR content into the HDR pixel values having the characteristic
of the HDR content outputtable on the display apparatus 200, by using the acquired
content conversion information.
[0125] According to an exemplary embodiment, HDR pixel values having a characteristic of
an HDR content outputtable on the display apparatus 200 may be set in order to respectively
correspond to SDR pixel values of each image frame of an SDR content. Therefore, the
content outputting apparatus 100 may convert the SDR content into a content having
the characteristic of the HDR content outputtable on the display apparatus 200 by
using the HDR pixel values respectively corresponding to the SDR pixel values of each
image frame of the SDR content based on a lookup table included in content conversion
information.
[0126] According to another exemplary embodiment, HDR pixel values having a characteristic
of an HDR content outputtable on the display apparatus 200 may be set in order to
corresponding to selected SDR pixel values of each image frame of an SDR content.
In this case, the content outputting apparatus 100 determines HDR pixel values corresponding
to other SDR pixel values from HDR pixel values corresponding to the selected SDR
pixel values based on a lookup table included in content conversion information. The
content outputting apparatus 100 may convert the SDR content into a content having
a characteristic of an HDR content outputtable on the display apparatus 200 by using
the HDR pixel values corresponding to the selected SDR pixel values and the HDR pixel
values determined in relation to the other SDR pixel values.
[0127] The content outputting apparatus 100 transmits the content converted to have the
characteristic of the HDR content outputtable on the display apparatus 200 in relation
to the SDR content to the display apparatus 200.
[0128] Here, the content outputting apparatus 100 may transmit content information including
information for gamma-correcting the corresponding content in the display apparatus
200 along with the content converted to have the characteristic of the HDR content
to the display apparatus 200. Therefore, the display apparatus 200 may gamma-correct
the content converted to have the characteristic of the HDR content based on the gamma
information included in the content information received from the content outputting
apparatus 100, signal process the gamma-corrected content in a form that may be output,
and display the signal-processed content.
[0129] However, the exemplary embodiments are not limited thereto, and the content outputting
apparatus 100 may transmit the content information including null information for
gamma-correcting the corresponding content in the display apparatus 200 along with
the content converted to have the characteristic of the HDR content to the display
apparatus 200. If the content information including the null information is received,
the display apparatus 200 may gamma-correct the content converted to have the characteristic
of the HDR content by using default gamma information, signal-process the gamma-corrected
content in a form that may be output, and display the signal-processed content.
[0130] If EDID is received from the display apparatus 200, the content outputting apparatus
100 may determine whether the display apparatus 200 is capable of playing an HDR content,
based on the received EDID before converting the SDR content into the content having
the characteristic of the HDR content. Here, the EDID may be content-playing-related
specification information of the display apparatus 200. If the display apparatus 200
is determined to be capable of playing the HDR content based on the EDID, the content
outputting apparatus 100 may convert the SDR content into the content having the characteristic
of the HDR content.
[0131] The EDID received from the display apparatus 200 may include information for gamma-correcting
the HDR content. In this case, the content outputting apparatus 100 may acquire content
conversion information from a plurality of pieces of pre-stored content conversion
information based on gamma information acquired from VUI or SEI of metadata of the
SDR content and gamma information included in the EDID. The content outputting apparatus
100 determines HDR pixel values corresponding to SDR pixel values of each image frame
of the SDR content from the acquired content conversion information. The content outputting
apparatus 100 may convert the SDR content into the content having the characteristic
of the HDR content outputtable on the display apparatus 200 by using HDR pixel values
respectively corresponding to SDR pixel values of each image frame of the SDR content
and transmit the content to the display apparatus 200.
[0132] Therefore, the display apparatus 200 may gamma-correct the content converted to have
the characteristic of the HDR content received from the content outputting apparatus
100 by using preset gamma information, signal-process the gamma-corrected content
in a form that may be output, and display the signal-processed content.
[0133] A process performed according to an exemplary embodiment may be stored in program
form on a non-transitory computer readable medium. The non-transitory computer readable
medium may be a medium which does not store data temporarily such as a register, cache,
and memory, but instead stores data semi-permanently and is readable by devices.
[0134] The foregoing exemplary embodiments and advantages are merely exemplary and are not
to be construed as limiting the present invention. The present teaching can be readily
applied to other types of apparatuses. Also, the description of the exemplary embodiments
is intended to be illustrative, and not to limit the scope of the claims, and many
alternatives, modifications, and variations will be apparent to those skilled in the
art.